Cat® Machine Linkage Pins support rotational movement between machine frames, linkages and work tools. They are found wherever rotation must occur between two structures. Genuine Cat Pins and Sleeve Bearings are specifically designed to operate as a system to deliver the performance you expect. Caterpillar design engineers match the right combination of dimensions, materials, heat treatment, surface treatments and finish to each part to enable them to work and wear effectively with all the other neighboring and dependent parts.